56 lines
1.6 KiB
JavaScript
56 lines
1.6 KiB
JavaScript
(function (exports) {
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'use strict';
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var variationsWithRepetion = (function () {
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var res;
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function variations(arr, k, index, current) {
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if (k === index) {
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return res.push(current.slice());
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}
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for (var i = 0; i < arr.length; i += 1) {
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current[index] = arr[i];
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variations(arr, k, index + 1, current);
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}
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}
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/**
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* Finds all the variations with repetition of given array.<br><br>
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* Variations with repetition is the number of ways to sample k elements
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* from a set of elements (which may be repeated).
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*
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* @example
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* var variations = require('path-to-algorithms/src/combinatorics/' +
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* 'variations-repetition').variationsWithRepetion;
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* var result = variations(['apple', 'orange', 'pear'], 2);
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*
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* // [['apple', 'apple'],
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* // ['apple', 'orange'],
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* // ['apple', 'pear'],
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* // ['orange', 'apple'],
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* // ['orange', 'orange'],
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* // ['orange', 'pear'],
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* // ['pear', 'apple'],
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* // ['pear', 'orange'],
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* // ['pear', 'pear']]
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* console.log(result);
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*
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* @module combinatorics/variations-repetition
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* @public
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* @param arr {Array} Set of items.
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* @param k {Number} Size of each combination.
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* @return {Array} Returns all combinations.
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*/
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return function (arr, k) {
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res = [];
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variations(arr, k, 0, []);
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var temp = res;
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res = undefined;
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return temp;
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};
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}());
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exports.variationsWithRepetion = variationsWithRepetion;
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}((typeof window === 'undefined') ? module.exports : window));
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